The investigation outlined in this supplemental grant proposal has as its objective the expansion of work in progress concerned with the isolation and screening of new potential anti-tumor alkaloids. Samples of 17 rare species of South American Menispermaceae will be made available to us from the personal collection of B. A. Krukoff, the world's botanical authority in this field. Plants from this collection are representative of the genera Curarea, Telitoxicum, Abuta, Caryomene, Anomospermum, and Orthomene.